A small, sealable enclosure which reclaimed moisture from the breath of occupants.

Although the Fremen of Dune had stillsuits, which allowed them to roam the surface of the planet without losing much moisture from their bodies, there were times when wearing the suits was inconvenient. For example, when camped, stilltents afforded the opportunity for relaxation.

Bits of solid reality began to dip through the dream state into his awareness. He knew suddenly that he was in a hiereg, a desert camp. Chani had planted their stilltent on flour-sand for its softness. He saw Chani in the grayness, matching him movement for movement, securing her stillsuit for the open desert. He kissed her palm before securing the faceflap of his suit, then turned and cracked the seal of the tent. The air that came in to them held the chill not-quite-dryness that would precipitate trace dew in the dawn.